Declaring e-mail past its prime in the age of texts and instant messages, CEO Mark Zuckerberg said the company doesn't believe e-mail is going to be a modern messaging system. The first Internet e-mail system arrived in the early 1970s.

"If we do a good job, some people will say this is the way that the future will work," Zuckerberg said.

Zuckerberg dismissed notions that "Project Titan," as its service is called, is the "Gmail killer" it's been dubbed as in the press. But he also said that just as high school students are forgoing e-mail in favor of shorter, more immediate chats, more people down the line will send IMs and chats because it's simpler, "more fun" and more valuable to use.

Though e-mail is still a primary form of communication for older adults, recent studies suggest this is not the case for young people. Text messaging has surpassed face-to-face contact, e-mail, phone calls and instant messaging as the primary form of communication for U.S. teens, according to a 2009 survey from the Pew Internet & American Life Project.

E-mail use was the lowest — only 11 percent of teens said they use it every day to interact with friends, compared with 54 percent who said they text daily and 30 percent who said they use landline phones.

The popular social network unveiled its plans in San Francisco on Monday, a day before Zuckerberg speaks at the Web 2.0 Summit in San Francisco.

Underscoring the enormity of the project, Facebook's director of engineering, Andrew "Boz" Bosworth, said 15 Facebook engineers worked on the project for 15 months.